The present invention relates to a collision object protection device, which absorbs an impact of a collision object such as a pedestrian upon collision with a vehicle, and protects the collision object.
Recently, there has been proposed a collision object protection device which inflates and expands an air bag on a vehicle if a collision of the collision object with the vehicle is detected or predicted, so that an impact force applied to the collision object is absorbed and relieved. Such a collision object protection device is disclosed, for example, by Japanese Laid-open Patent Application No. 2000-264146 (paragraph [0015] and FIG. 4), and includes an air bag substantially in the form of a letter “U” consisting of a main body portion which covers a lower part of the front windshield glass of the vehicle, a pair of pillar base portions formed on both sides of the main body portion, and a pair of pillar portions which expand from the respective pillar base portions and cover both right and left side portions (front pillars, etc.) of the front windshield glass. The air bag is compactly housed in a space below and at the center of the lower part of the front windshield glass with the respective pillar portions folded up where necessary and with the right and left ends of the main body portion folded back to the center. The air bag is inflated and expanded when an inflator supplies a gas to the main body portion of the air bag. The air bag is fixed to the vehicle such that a portion near the center of the main body portion is attached to the inflator.
However, in the conventional collision object protection device, when the inflator injects the gas into the main body portion of the air bag which is folded back and housed to inflate and expand the air bag on the front windshield glass of the vehicle, the pillar base portions or the pillar portions often expand before the main body portion sufficiently expands. As a result, flapping causes on a part of the pillar portion during the expansion of the air bag. This leads to a difficulty in stably positioning the air bag to a predetermined position.
Further, the gas is injected from the inflator near the center of the main body portion, so that flows of the gas toward the both side portions of the main body portion lift up the pillar base portions in a direction away from the vehicle body. Therefore, the pillar portions extending from the pillar base portions rise up from the vehicle body during the expansion of the air bag. Due to this state, if the air bag is subject to a crosswind or the like, the air bag is disadvantageously moved off from the predetermined position.
In other words, according to the conventional collision object protection device, it is not possible for the inflated and expanded air bag to stably cover the intended protection area. In view of the above, the present invention seeks to provide a collision object protection device which enables the inflated and expanded air bag to stably cover the intended protection area.